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Hey Ray! Using Pizza Pies To Explain Pi Day

PITTSBURGH (KDKA) -- Pi Day is coming up to celebrate Pi. You know, that number from math class that is 3.1415926535 8 and so forth. I figured since March 14th, or Pi Day is coming up, we would use one of the most popular "pies" to show how Pi works. The pizza pie!

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(Photo Credit: KDKA)
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(Photo Credit: KDKA)

We are going to use four pizzas for our experiment. If you try to reproduce this one, make sure you have a lot of hungry scientists nearby!

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(Photo Courtesy Ray Petelin)

Simply, Pi is the ratio of the circumference of a circle to its diameter. That ratio is 3.14 and all those repeating numbers.

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(Photo Courtesy Ray Petelin)

We cut the circumference off of one pizza at the beginning of this. Remember, circumference is the distance around a circle. Remember, Pi is the relationship of the circumference of the diameter of a circle. The diameter is the distance across the center of the circle.

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(Photo Credit: KDKA)

We are going to use the crust to show this relationship in real life.

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(Photo Courtesy Ray Petelin)

Since we have the circumference cut off of one pizza, we can lay it in a straight line across the other pizzas. You will see that the circumference, or crust, we cut off stretches across three, full pizzas of similar size with a little hanging over. As a decimal, that is 3.14, or Pi!

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